Time domain multiplexing (TDM) in the optical domain (or “OTDM”) is a key enabling technology for the next generation all optical networks. The ability to exploit TDM independently of signal format and bit rate is a crucial step in realizing a completely transparent all optical network. Because an all-optical network in general does not need to “know” the bit rate or signal format of a particular signal it transmits, bit rate and format independent OTDM is a natural fit. What will be addressed herein relates to synchronous OTDM. In order to accomplish synchronous OTDM, N input signals at a given clock rate must be upconverted and interleaved to form a multiplexed output signal. To do this all optically, various clock conversions, modulations and clock gap creations must be accomplished solely in the optical domain, as explained below.